The nature of synthetic judgements a priori and the categorical imperative

Abstract

This thesis attempts to show that the five different formulations of the categorical imperative that Kant provides are all equivalent, in spite of their apparently differing meanings. To meet this goal I propose to display the nature of synthetic judgements a priori, since Kant claimed that the categorical imperative was this sort of judgement. This requires examining Kant's exposition of synthetic judgements a priori in mathematics and natural science in the Critique of Pure Reason, where he dealt with them at length. After showing that there can be no subject-object distinction with regard to synthetic judgements a priori, in either mathematics or natural science, I apply this moral to Kant's formulations of the categorical imperative in The Foundations of the Metaphysics of Morals and the Critique of Practical Reason, from which perspective I try to reveal that, at the relevant level of abstraction, there are no real differences between these formulations.